An exaggerated blood pressure response to mental stress is believed to characterize young adults with genetic risk of essential hypertension, suggesting that stress-induced changes might provide a useful index of pathogenetic processes. We explored this by studying pressor responsivity to competitive tasks in adolescents drawn from a large urban population. Individuals with systolic or diastolic pressures persistently between the 85th and 95th percentiles were evaluated on basal blood pressure, parental history of hypertension, and pressor and heart rate response to a challenging video game. Basal pressure was measured again at 6, 10, and 14 months. A persistently diminished pulse pressure was the cardiovascular characteristic that most reliably typified normotensive subjects with familial hypertension. Response to the video game was the best indicator of risk status. Contrary to expectations derived from research with convenience samples, epidemiologic investigation points to an increased peripheral resistance and lower cardiac output as the cardiovascular pattern more prominently associated with genetic risk in the normotensive adolescent.